Familyman, to answer some of the questions you raised about the Kioti CK line, yes the CK30/35 hst will handle a 6' box blade, but you will be in low range pulling it if the rippers are fully down, otherwise you'll be OK. I'm not sure about the proper size finishing mower, but I believe the reason for the larger decrease in PTO power is a result of the additional weight of the tractor that requires more power to move it.
I had a CK30hst. I really liked it, but had lots of small issues with it. According to members on TBN, my experience is not normal and I probably got a bit of a lemon.
I have now traded to a DK45hst. The DK line is a totally different beast. I thought the CK line was luxurious, and I still do compared to similar tractors, but man, the DK is so nice and smooth, with awesome features and incredible power. The KL401 loader is unbelievable, I'm just having a hard time keeping the rear wheels on the ground, and they're loaded and my box blade is on the back.
The CK27 and CK30 are very close in price, and I would choose the CK30. The CK35 seems to be a lot more expensive, even though it's identical with a few more hp. It's not worth the upgrade in my mind. If you are looking at the CK35, ask how much a DK40 would be. The DK's will amaze you for their refinement, features and strength.